Three discs A, B and C having radii 2 m, 4 m and 6 m respectively are coated with carbon black on their outer surfaces. - The wavelengths corresponding to maximum intensity are 300 nm, 400 nm and 500 nm respectively. The power radiated by them are Q_A , Q_B and Q_C respectively:

• A

  Q_A is maximum

• B

  Q_B is maximum

• C

  Q_C is maximum

• D

  Q_A = Q_B = Q_C